Chapter 21 Temperature Measurement of FBs-PLC and PID Control

FUN86
TPCTL
Convenient Instruction of PID Temperature Control
FUN86
TPCTL
● In the mean time, this instruction will also check whether highest temperature warning (the register for the
set point of highest temperature warning is R4008). When successively scanning for ten times the current
values of measured temperature are all higher than or equal to the highest warning set point, the warning bit
will set to be ON and instruction output “ALM” will be ON. This can avoid the safety problem aroused from
temperature out of control, in case the SSR or heating circuit becomes short.
● This instruction can also detect the unable to heat problem resulting from the SSR or heating circuit runs
open, or the obsolete heating band. When output of temperature control turns to be large power (set in
R4006 register) successively in a certain time (set in R4007 register), and can not make current
temperature fall in desired range, the warning bit will set to be ON and instruction output “ALM” will be ON.
● WR: Starting of working register for this instruction. It takes 9 registers and can’t be repeated in using.
The content of the two registers WR+0 and WR+1 indicating that whether the current temperature falls
within the deviation range (stored in registers starting from Os). If it falls in the deviation range,the
in-zone bit of that point will be set ON; if not, the in-zone bit of that point will be cleared OFF.
Bit definition of WR+0 explained as follows:
Bit0=1, it represents that the temperature of the Sn+0 point is in-zone…
Bit15=1, it represents that the temperature of the Sn+15 point is in-zone.
Bit definition of WR+1 explained as follows:
Bit0=1, it represents that the temperature of the Sn+16 point is in-zone…
Bit15=1, it represents that the temperature of Sn+31 point is in-zone.
The content of the two registers WR+2 and WR+3 are the warning bit registers, they indiacte that whether
there exists the highest temperature warning or heating circuit opened.
Bit definition of WR+2 explained as follows:
Bit0=1, it means that there exists the highest warning or heating circuit opened at the Sn+0 point...
Bit15=1, it means that there exists the highest warning or heating circuit opened at the Sn+15 point.
Bit definition of WR+11 explained as follows:
Bit0=1, it means that there exists the highest warning or heating circuit opened at the Sn+16 point...
Bit15=1 , it means that there exists the highest warning or heating circuit opened at the Sn+31 point.
Registers of WR+4 ~ WR+8 are used by this instruction.
● It needs separate instructions to perform the heating or cooling control.
Specific registers related to FUN86
● R4005 : The content of Low Byte to define the solution interval between PID calculation
=0, perform the PID calculation evey 1 seconds.
=1, perform the PID calculation evey 2 seconds.
=2, perform the PID calculation evey 4 seconds. (System default)
=3, perform the PID calculation evey 8 seconds.
=4, perform the PID calculation evey 16 seconds.
≥5, perform the PID calculation evey 32 second
: The content of High Byte to define the cycle time of PID ON/OFF(PWM)output.
=0,PWM cycle time is 1 seconds.
=1,PWM cycle time is 2 seconds. (System default)
=2,PWM cycle time is 4 seconds.
=3,PWM cycle time is 8 seconds.
=4,PWM cycle time is 16 seconds.
≥5,PWM cycle time is 32 second.
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